1. Field of the Invention
The present invention relates to a system and method for making information concerning a vehicle characteristic and introducing it to an object vehicle so as to change the characteristics thereof.
2. Description of the Prior Art
Generally, a vehicle characteristic is provided so as to satisfy the driver's taste wherever the vehicle runs, whatever driving circumstances are and whatever the driver's personality is.
It has been known that the vehicle is provided with a manual switch for selecting a hard mode or soft mode of active suspension system and for sporty mode or normal mode of four wheel steering system by setting a specific control gain. This enables the vehicle running characteristic to match the driver's taste.
However, the conventional vehicle with such a manual switch is not enough to satisfy an average driver's desire. In view this, a learning control vehicle has been proposed that the driver's taste embodied in operation is learned for a feedback control and change a control gain of the running characteristic of the vehicle.
Japanese Patent Publication No. 3-44029, published for opposition on 1990, discloses a learning control vehicle in which a steering ratio between the front and rear wheels is changed based on the mean value of steering angle change speed, steering angle, yawing rate, side acceleration in a predetermined time period of the steering operation.
With the control gain change system as proposed conventionally, a part of the vehicle running characteristics is able to be changed. However, this is not able to change the vehicle characteristics systematically with regard to driving mechanisms such as the steering mechanism, suspension system, braking system in response to the driver's feeling and taste. In order to meet the driver's feeling or taste, it is necessary for the vehicle to have various sensors and control unit for processing signals from the sensors and learning features of the driver's operation to change the vehicle characteristics.
It should, however, be noted that each vehicle is necessary to be equipped with the various sensors and control unit with a complicate software and a large scale of memory for processing a large amount of the information from the sensors as well as the learning system for making the learning control. Specifically, it is necessary for each vehicle to increase the capacity of RAM for processing data of the learning control. This would raise the vehicle price.